Monthly Spotlight

Development of New Energy-saving Tankers

Electric podded propulsors of the non ballast tanker move up and down.

Professor Yoshiho Ikeda

Ships have been an important method of transportation for Japanese people and materials since ancient times. Surrounded by sea, 99.7 percent of Japan's import and export volume now depends on transportation by ship.

"Shipbuilding plays a significant role in the Japanese economy because the ship-building tonnage of three East Asian countries - Japan, Korea and China accounts for 90 percent of the world's total. With the constant advancement of ship technologies and a doubling of energy efficiency over the past decades, fuel consumption of ships has reduced by 50 percent since the so-called Oil Shock in 1973," says Yoshiho Ikeda, Dean and Professor at the Graduate School of Engineering. Now researchers and engineers in the field are attempting to reduce fuel consumption by an additional 50 percent in an effort to further improve energy efficiency.

Professor Ikeda's study team is currently working on the development of an energy-saving tanker that instead of using ballast water to increase stability will use electric podded propulsors that can move up and down. In light load conditions the tanker will float higher in the water and so the podded propulsors will move down in the water enabling the tanker to still receive maximum propulsion performance. The elimination of ballast water and a higher floating tanker can enable an expected 40 percent decrease in frictional resistance in light load conditions due to a reduced wetted surface. Another improvement for higher energy efficiency is a stream-lined hull shape that can reduce viscous pressure resistance. These particular specifications will be a game changer for the realization of a super energy saving tanker.

"We are committed to making step by step efforts till they pay off, some decades in the future. The next generation of ships will be born from such decades-long dreams."